/****************************************************************************
* binfmt/elf.c
*
* Copyright (C) 2012 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <stdint.h>
#include <string.h>
#include <elf.h>
#include <debug.h>
#include <errno.h>
#include <arpa/inet.h>
#include <nuttx/binfmt.h>
#include <nuttx/elf.h>
#ifdef CONFIG_ELF
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* CONFIG_DEBUG, CONFIG_DEBUG_VERBOSE, and CONFIG_DEBUG_BINFMT have to be
* defined or CONFIG_ELF_DUMPBUFFER does nothing.
*/
#if !defined(CONFIG_DEBUG_VERBOSE) || !defined (CONFIG_DEBUG_BINFMT)
# undef CONFIG_ELF_DUMPBUFFER
#endif
#ifdef CONFIG_ELF_DUMPBUFFER
# define elf_dumpbuffer(m,b,n) bvdbgdumpbuffer(m,b,n)
#else
# define elf_dumpbuffer(m,b,n)
#endif
#ifndef MIN
# define MIN(a,b) (a < b ? a : b)
#endif
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static int elf_loadbinary(FAR struct binary_s *binp);
#if defined(CONFIG_DEBUG) && defined(CONFIG_DEBUG_BINFMT)
static void elf_dumploadinfo(FAR struct elf_loadinfo_s *loadinfo);
#endif
/****************************************************************************
* Private Data
****************************************************************************/
static struct binfmt_s g_elfbinfmt =
{
NULL, /* next */
elf_loadbinary, /* load */
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: elf_dumploadinfo
****************************************************************************/
#if defined(CONFIG_DEBUG) && defined(CONFIG_DEBUG_BINFMT)
static void elf_dumploadinfo(FAR struct elf_loadinfo_s *loadinfo)
{
unsigned long dsize = loadinfo->datasize + loadinfo->bsssize;
bdbg("LOAD_INFO:\n");
bdbg(" ISPACE:\n");
bdbg(" ispace: %08lx\n", loadinfo->ispace);
bdbg(" entryoffs: %08lx\n", loadinfo->entryoffs);
bdbg(" isize: %08lx\n", loadinfo->isize);
bdbg(" DSPACE:\n");
bdbg(" dspace: %08lx\n", loadinfo->dspace);
if (loadinfo->dspace != NULL)
{
bdbg(" crefs: %d\n", loadinfo->dspace->crefs);
bdbg(" region: %08lx\n", loadinfo->dspace->region);
}
bdbg(" datasize: %08lx\n", loadinfo->datasize);
bdbg(" bsssize: %08lx\n", loadinfo->bsssize);
bdbg(" (pad): %08lx\n", loadinfo->dsize - dsize);
bdbg(" stacksize: %08lx\n", loadinfo->stacksize);
bdbg(" dsize: %08lx\n", loadinfo->dsize);
bdbg(" RELOCS:\n");
bdbg(" relocstart: %08lx\n", loadinfo->relocstart);
bdbg(" reloccount: %d\n", loadinfo->reloccount);
bdbg(" HANDLES:\n");
bdbg(" filfd: %d\n", loadinfo->filfd);
}
#else
# define elf_dumploadinfo(i)
#endif
/****************************************************************************
* Name: elf_loadbinary
*
* Description:
* Verify that the file is an ELF binary and, if so, load the ELF
* binary into memory
*
****************************************************************************/
static int elf_loadbinary(struct binary_s *binp)
{
struct elf_loadinfo_s loadinfo; /* Contains globals for libelf */
int ret;
bvdbg("Loading file: %s\n", binp->filename);
/* Initialize the xflat library to load the program binary. */
ret = elf_init(binp->filename, &loadinfo);
elf_dumploadinfo(&loadinfo);
if (ret != 0)
{
bdbg("Failed to initialize for load of NXFLT program: %d\n", ret);
goto errout;
}
/* Load the program binary */
ret = elf_load(&loadinfo);
elf_dumploadinfo(&loadinfo);
if (ret != 0)
{
bdbg("Failed to load NXFLT program binary: %d\n", ret);
goto errout_with_init;
}
/* Bind the program to the exported symbol table */
ret = elf_bind(&loadinfo, binp->exports, binp->nexports);
if (ret != 0)
{
bdbg("Failed to bind symbols program binary: %d\n", ret);
goto errout_with_load;
}
/* Return the load information */
binp->entrypt = (main_t)(loadinfo.ispace + loadinfo.entryoffs);
binp->ispace = (void*)loadinfo.ispace;
binp->dspace = (void*)loadinfo.dspace;
binp->isize = loadinfo.isize;
binp->stacksize = loadinfo.stacksize;
elf_dumpbuffer("Entry code", (FAR const uint8_t*)binp->entrypt,
MIN(binp->isize - loadinfo.entryoffs,512));
elf_uninit(&loadinfo);
return OK;
errout_with_load:
elf_unload(&loadinfo);
errout_with_init:
elf_uninit(&loadinfo);
errout:
return ret;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: elf_initialize
*
* Description:
* ELF support is built unconditionally. However, it order to
* use this binary format, this function must be called during system
* format in order to register the ELF binary format.
*
* Returned Value:
* This is a NuttX internal function so it follows the convention that
* 0 (OK) is returned on success and a negated errno is returned on
* failure.
*
****************************************************************************/
int elf_initialize(void)
{
int ret;
/* Register ourselves as a binfmt loader */
bvdbg("Registering ELF\n");
ret = register_binfmt(&g_elfbinfmt);
if (ret != 0)
{
bdbg("Failed to register binfmt: %d\n", ret);
}
return ret;
}
/****************************************************************************
* Name: elf_uninitialize
*
* Description:
* Unregister the ELF binary loader
*
* Returned Value:
* None
*
****************************************************************************/
void elf_uninitialize(void)
{
unregister_binfmt(&g_elfbinfmt);
}
#endif /* CONFIG_ELF */
